The pulvinar nucleus of the thalamus receives inputs from striate cortex and superior colliculus, and has broad interconnections with parietal and temporal association cortex. In the work proposed here, the functional properties of neurons in the pulvinar will be investigated using microelectrode, single unit techniques in unanesthetized, freely moving monkeys. Visual stimuli of various shapes, contrasts, colors, orientations and movement velocities will be presented, and tones, tactile stimulation and joint rotations will be used to assess possible input to these neurons from other sensory modalities. The importance of motivation and behavioral performance on the response of these neurons will also be investigated. Results from these experiments will lay the foundation for future work into the functional importance of the pulvinar in visual perception, in particular, and for investigations on the interdependence of this nucleus and the cerebral cortex.